THC Electrochemical Sensors Must Address Matrix Interference as Well as Detection Sensitivity
A 2022 narrative review found promise in rapid electrochemical THC detection while identifying nonspecific interactions and matrix interference as major challenges. A low detection limit alone does not establish reliable performance in a real biological specimen.
The reviewed applications were diverse
The review considered synthetic samples, plant material and oral fluid. These are different analytical environments. A sensor that performs well in a prepared solution has not thereby demonstrated equivalent behavior in oral fluid containing other chemical constituents.
Sensitivity and selectivity answer different questions
Sensitivity concerns the response to the target under tested conditions. Selectivity concerns distinguishing that response from other influences. Improving one does not necessarily resolve the other, particularly when a surface coating can interact with compounds in the specimen.
Storage and reuse introduce additional demands
The review noted special storage needs for sensors modified with proteins or antibodies and identified durable, reusable sensors as a research priority. A strong initial response is not the same as stable performance over the device's intended working life.
Interpreting the evidence
A forensic technology assessment should retain the tested matrix, interference experiments and storage conditions beside the detection limit. This synthesis supports further analytical development. It does not establish that all promising prototypes are ready for roadside use or can measure impairment from a chemical signal.
Related reading: interpreting cannabis tolerance claims.
Research reference
Kaveh Amini; Ali Sepehrifard; Ali Valinasabpouri; Jennifer Safruk; Davide Angelone; Tiago de Campos Lourenco (2022). Recent advances in electrochemical sensor technologies for THC detection—a narrative review. Journal of Cannabis Research. doi:10.1186/s42238-022-00122-3.
This discussion draws on the abstract and introductory material in the supplied research synthesis.



